Total Syntheses of a Family of Cadinane Sesquiterpenes

Concise
total syntheses of (−)-(1R,6S,7S,10R)-hydroxy­cadinan-3-en-5-one
(1), (+)-(1R,5S,6R,7S,10R)-cadinan-3-ene-1,5-diol
(2), and (+)-(1R,5S,6R,7S,10R)-cadinan-4­(11)-ene-1,5-diol
(3), three cadinane sesquiterpenes sharing identical trans-decalin carbon skeletons yet containing different
oxidation states and substitution patterns, are reported. They were
prepared from a common trans-decalin intermediate,
which was readily prepared on gram scale through an aldol-Henry reaction
cascade and oxidation sequence.